Supplemental Cash Flow Information -Supplemental Cash Flow (Details) - USD ($) $ in Millions	9 Months Ended
Feb. 28, 2019	Feb. 28, 2018
Supplemental Cash Flow Information [Abstract]
Interest (net of capitalized interest)	$ 498	$ 430
Income taxes	346	707
Income tax refunds received	(34)	(59)
Cash tax payments, net	$ 312	$ 648

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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-Name Accounting Standards Codification
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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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-Publisher FASB
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- Definition

The amount of cash received during the period as refunds for the overpayment of taxes.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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No definition available.

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